Storage class memory （SCM） has the potential to revolutionize the memory landscape by its non-volatile and byte-addressable properties. However, there is little published work about exploring its usage for modem vir...Storage class memory （SCM） has the potential to revolutionize the memory landscape by its non-volatile and byte-addressable properties. However, there is little published work about exploring its usage for modem virtualized cloud infrastructure. We propose SCM-vWrite, a novel architecture designed around SCM, to ease the performance interference of virtualized storage subsystem. Through a case study on a typical virtualized cloud system, we first describe why cur- rent writeback manners are not suitable for a virtualized en- vironment, then design and implement SCM-vWrite to im- prove this problem. We also use typical benchmarks and re- alistic workloads to evaluate its performance. Compared with the traditional method on a conventional architecture, the ex- perimental result shows that SCM-vWrite can coordinate the writeback flows more effectively among multiple co-located vip operating systems, achieving a better disk I/O perfor- mance without any loss of reliability.展开更多
Multispecies microbial mixed fermentation is crucial for the formation of flavors in soy sauce.The present study applied metagenomic strategies to uncover the metabolic network for flavors formation in the non-Cantone...Multispecies microbial mixed fermentation is crucial for the formation of flavors in soy sauce.The present study applied metagenomic strategies to uncover the metabolic network for flavors formation in the non-Cantonese soy sauce in China.Twenty-nine major flavor compounds were identified by GC-MS and HPLC,representing the typical flavor compounds of the non-Cantonese soy sauce,including 3 organic acids,8 amino acids,and 18 volatile compounds.Metagenomic sequencing and KEGG enrichment analysis revealed the specific functional microbiome,which constituted seven major flavor compounds associated genera,namely Leuconostoc,Staphylococcus,Tetragenococcus,Weissella,Aspergillus,Wickerhamycesa,and Zygosaccharomyces.Aspergillus was primarily responsible for the degradation of raw materials in the early fermentation stage,including the degradation of cellulose and lecithin.It also played an irreplaceable role in the formation of 1-octene-3-ol.Weissella,Staphylococcus,and Leuconostoc played essential metabolic roles in the whole fermentation process,particularly in the metabolism of amino acids and the formation of alcohols.Staphylococcus also participated in the degradation of nitrite/nitrate.Tetragenococcus became the dominant bacteria with the highest relative abundance in the late fermentation stage,which was mainly responsible for the synthesis of acetic acid,lactic acid,and other acids.Additionally,Wickerhamycesa and Zygosaccharomyces also contributed to the formation of alcohols,acids,and aldehydes during the late fermentation stage.This study provides a deeper understanding of the diverse roles in the flavor formation of microorganisms during the traditional condiment soy sauce fermentation process.展开更多
Memory copying is one of the most common operations in modern software.Usually,the operation reflects a synchronous(sync)CPU procedure of memory copying,incurring overheads such as cache pollution and CPU stalling,esp...Memory copying is one of the most common operations in modern software.Usually,the operation reflects a synchronous(sync)CPU procedure of memory copying,incurring overheads such as cache pollution and CPU stalling,especially in the scenario of bulk copying with large data.To improve this issue,some works based on I/OAT,which is a dedicated and popular hardware copying engine on Intel platform,is proposed but still exists several problems:(1)lacking atomic allocation/revocation at the granularity of I/OAT channel;(2)deficiency of interrupt support and(3)complicated programming interfaces.We propose RAMCI,an asynchronous(async)memory copying mechanism based on Intel I/OAT engine,not only improves the sync overheads,but also overcomes the above three issues through(1)a lock mechanism by using lowlevel CAS instruction;(2)a lightweight interrupt mechanism for the completion of memory copying,instead of using the polling pattern which consuming large CPU resource and(3)a group of well-defined and abstract interfaces,allowing the programmers to utilize the underlying free I/OAT channels transparently.To support the interfaces,a novel scheduler of the I/OAT channels is introduced.It splits the source copying data into several pieces,and each of them can be allocated with a dedicated I/OAT channel intelligently to transfer the data with parallelism.We evaluate RAMCI and compare it with other memory copying mechanisms in four NUMA scenarios.The experimental results show that RAMCI improves memory copying performance up to 4.68×while achieving almost full ability of parallel computing.展开更多
文摘Storage class memory （SCM） has the potential to revolutionize the memory landscape by its non-volatile and byte-addressable properties. However, there is little published work about exploring its usage for modem virtualized cloud infrastructure. We propose SCM-vWrite, a novel architecture designed around SCM, to ease the performance interference of virtualized storage subsystem. Through a case study on a typical virtualized cloud system, we first describe why cur- rent writeback manners are not suitable for a virtualized en- vironment, then design and implement SCM-vWrite to im- prove this problem. We also use typical benchmarks and re- alistic workloads to evaluate its performance. Compared with the traditional method on a conventional architecture, the ex- perimental result shows that SCM-vWrite can coordinate the writeback flows more effectively among multiple co-located vip operating systems, achieving a better disk I/O perfor- mance without any loss of reliability.
基金the financial support from the Program of Introducing Talents of Discipline to Universities(111 Project)(111-2-06).
文摘Multispecies microbial mixed fermentation is crucial for the formation of flavors in soy sauce.The present study applied metagenomic strategies to uncover the metabolic network for flavors formation in the non-Cantonese soy sauce in China.Twenty-nine major flavor compounds were identified by GC-MS and HPLC,representing the typical flavor compounds of the non-Cantonese soy sauce,including 3 organic acids,8 amino acids,and 18 volatile compounds.Metagenomic sequencing and KEGG enrichment analysis revealed the specific functional microbiome,which constituted seven major flavor compounds associated genera,namely Leuconostoc,Staphylococcus,Tetragenococcus,Weissella,Aspergillus,Wickerhamycesa,and Zygosaccharomyces.Aspergillus was primarily responsible for the degradation of raw materials in the early fermentation stage,including the degradation of cellulose and lecithin.It also played an irreplaceable role in the formation of 1-octene-3-ol.Weissella,Staphylococcus,and Leuconostoc played essential metabolic roles in the whole fermentation process,particularly in the metabolism of amino acids and the formation of alcohols.Staphylococcus also participated in the degradation of nitrite/nitrate.Tetragenococcus became the dominant bacteria with the highest relative abundance in the late fermentation stage,which was mainly responsible for the synthesis of acetic acid,lactic acid,and other acids.Additionally,Wickerhamycesa and Zygosaccharomyces also contributed to the formation of alcohols,acids,and aldehydes during the late fermentation stage.This study provides a deeper understanding of the diverse roles in the flavor formation of microorganisms during the traditional condiment soy sauce fermentation process.
基金funded by the National Natural Science Foundation of China under grant number 61972164,61772211 and U1811263the Guangdong Basic and Applied Basic Research Foundation under grant number 2019A1515011160the Guangzhou Key Laboratory of Big Data and Intelligent Education under grant number 201905010009.
文摘Memory copying is one of the most common operations in modern software.Usually,the operation reflects a synchronous(sync)CPU procedure of memory copying,incurring overheads such as cache pollution and CPU stalling,especially in the scenario of bulk copying with large data.To improve this issue,some works based on I/OAT,which is a dedicated and popular hardware copying engine on Intel platform,is proposed but still exists several problems:(1)lacking atomic allocation/revocation at the granularity of I/OAT channel;(2)deficiency of interrupt support and(3)complicated programming interfaces.We propose RAMCI,an asynchronous(async)memory copying mechanism based on Intel I/OAT engine,not only improves the sync overheads,but also overcomes the above three issues through(1)a lock mechanism by using lowlevel CAS instruction;(2)a lightweight interrupt mechanism for the completion of memory copying,instead of using the polling pattern which consuming large CPU resource and(3)a group of well-defined and abstract interfaces,allowing the programmers to utilize the underlying free I/OAT channels transparently.To support the interfaces,a novel scheduler of the I/OAT channels is introduced.It splits the source copying data into several pieces,and each of them can be allocated with a dedicated I/OAT channel intelligently to transfer the data with parallelism.We evaluate RAMCI and compare it with other memory copying mechanisms in four NUMA scenarios.The experimental results show that RAMCI improves memory copying performance up to 4.68×while achieving almost full ability of parallel computing.
